A global navigation satellite system (GNSS), such as the Global Positioning System (GPS), can be used to provide navigation information, e.g., position and velocity measurements for a sensor platform such as a vehicle, robot, or handheld device. When a GNSS is not available, an inertial navigation system (INS) can be used to provide the position and velocity measurements or estimates by using inertial sensors and an integration algorithm. Pure strap down inertial navigation has drift, that is, the errors in estimated position increase with time. A range finder can be used as an aiding source to address the drift. A range finder can provide 3D range data corresponding to a distance between the range finder and objects in front of the range finder. Features can be extracted from the 3D range data to aid the INS.